int select_loop(int svr_sock, t_select *slt_par, t_game *game)
{
t_svr_vector vec;
int err;
slt_cont = 1;
init_vector(&vec, slt_par);
while (slt_cont)
{
err = select(slt_par->fd_max, &(slt_par->fd_read), NULL, NULL,
slt_par->time);
if (err > 0)
{
if (FD_ISSET(svr_sock, &(slt_par->fd_read)))
if (add_client(&vec, slt_par, svr_sock) == EXIT_FAILURE)
fprintf(stderr, "add client error");
fetch_instr(&vec, slt_par, game);
}
end_loop(&vec, slt_par, game, svr_sock);
}
close_client(&vec, slt_par);
return (EXIT_SUCCESS);
}
// Execute an instruction cycle
// Fetch an instruction
// Decode the instruction opcode
// Execute the instruction
//
void instruction_cycle(CPU *cpu)
{
// Get current instruction to execute and its location,
// echo them out.
//
Address old_pc = cpu->pgm_counter;
fetch_instr(cpu);
printf("x%04hX: x%04hX ", old_pc, cpu->instr_reg);
// Execute instruction; set halt = 1 if execution is to stop
// (TRAP HALT or internal error).
//
switch ((cpu->instr_reg)) // ** Note ** place "op(cpu->instr_reg))"
{
case 0:
instr_BR(cpu);
break;
default:
printf("Bad opcode: %d; quitting\n", (cpu->instr_reg)); // ** Note ** place "op(cpu->instr_reg))"
cpu->running = 0;
}
}
//--------------------------------------------------------------------
// int cycle_model::fetch_operand(operand* op)
//
// returns the value of the operand
//
//--------------------------------------------------------------------
int cycle_model::fetch_operand(operand* op) {
switch(op->type) {
case o_acc: {
return A;
break;
}
case o_reg: {
assert((op->val<8)&&(op->val>=0));
#ifdef DEBUG
printf("read R%d=%d\n",op->val,R[op->val]);
#endif
return R[op->val];
break;
}
case o_dir: {
// fetch address
my_stack->address += 1;
int temp = fetch_instr(my_stack->address);
assert((op->val<INT_SIZE)&&(op->val>=0));
return int_mem[temp];
break;
}
case o_ind: {
assert((op->val==0)||(op->val==1));
assert((R[op->val]<INT_SIZE)&&(R[op->val]>=0));
return int_mem[R[op->val]];
break;
}
case o_ext: {
assert((op->val==1)||(op->val==0));
int addr = R[op->val];
assert((addr<MEM_SIZE)&&(addr>=0));
int result = fetch_data(addr);
return result;
break;
}
case o_cst: {
// fetch next byte
my_stack->address += 1;
int temp = fetch_instr(my_stack->address);
return temp;
break;
}
case o_lcst: {
// fetch next 2 bytes
my_stack->address += 1;
int temp = fetch_instr(my_stack->address);
my_stack->address += 1;
assert(my_stack->address<=MEM_SIZE);
temp = (temp<<8) + fetch_instr(my_stack->address);
return temp;
break;
}
case o_add: {
// fetch next byte
my_stack->address += 1;
int temp = ((op->val)<<8) + fetch_instr(my_stack->address);
return temp;
break;
}
case o_ladd: {
// fetch next 2 bytes
my_stack->address += 1;
int temp = fetch_instr(my_stack->address);
my_stack->address += 1;
temp = (temp<<8) + fetch_instr(my_stack->address);
return temp;
break;
}
case o_rel: {
// fetch next byte
my_stack->address += 1;
int temp = fetch_instr(my_stack->address);
if(temp<0x80)
return temp;
else
return -(0x100-temp);
break;
}
default: {
return -1;
break;
}
}
return -1;
}
void instruction_cycle(CPU *cpu, int order)
{
// Get current instruction to execute and its location,
// echo them out.
//
Address old_pc = cpu->memory[cpu->pgm_counter+1]; // OLD: cpu->pgm_counter
fetch_instr(cpu);
int op_code = 0;
u_reg = ((unsigned short int)(cpu->instr_reg));
op_code = u_reg/4096;
unsigned short movement1 = (old_pc << 4);
unsigned short movement2 = (old_pc << 7);
unsigned short movement3 = (old_pc << 12);
unsigned short movement4 = (old_pc << 7);
unsigned short movement5 = (old_pc << 13);
Commands.opCode = (old_pc >> 12); // Finished
Commands.intRest = (old_pc << 8); // Finished
Commands.trap = (Commands.intRest >> 8); // Finished
Commands.NZP = (movement1 >> 13);
Commands.offset = (movement2 >> 7);
Commands.last = (movement3 >> 12);
Commands.Src1 = (movement4 >> 6);
Commands.Src2 = (movement5 >> 13);
/* Tests
Output bit shifts
printf("\nShowing whats in memory, dividing integers:\n\n");
printf("First Hex: %hX\n", Commands.opCode);
printf("Second Hex: %hX\n", Commands.intSecond);
//printf("Remaining Hex: %hX\n", intRest);
printf("NZP value: %hX\n", Commands.NZP);
printf("offset value: %hX\n", Commands.offset);
printf("Trap value (last 2 digits): %hX\n", Commands.trap);
printf("Last value: %hX\n", Commands.last);
*/
// Execute instruction; set halt = 1 if execution is to stop
// (TRAP HALT or internal error).
//
switch ((Commands.opCode)) // ** Note ** place "op(cpu->instr_reg))"
{
case 0:
if (Commands.NZP > 0){
// Command loop that accounts for P and Z
// Removed because of the lack of time
/*if(Commands.NZP == 2){
printf("BRZ 3, CC = P, no go to\n");
//cpu->pgm_counter--;
}
else{ */
order ++;
printf("x%04X: x%04hX ", order, old_pc); // print location
cpu->pgm_counter = cpu->pgm_counter + Commands.last;
printf("BR %d, CC = Z, go to x%04X+%d = x%04X\n", Commands.last, order, (signed short)Commands.last, (order + Commands.last));
order = order + Commands.last;
}
else{
instr_BR(cpu);
}
break;
case 1:
printf("x%04X: x%04hX ", order, old_pc);
instr_ADD(cpu);
break;
case 2:
printf("x%04X: x%04hX ", order, old_pc);
instr_LD(cpu, order);
break;
case 3:
printf("x%04X: x%04hX ", order, old_pc);
instr_ST(cpu, order);
break;
case 4:
printf("x%04X: x%04hX ", order, old_pc);
instr_JSR(cpu);
break;
case 5:
printf("x%04X: x%04hX ", order, old_pc);
instr_AND(cpu);
break;
case 6:
printf("x%04X: x%04hX ", order, old_pc);
instr_LDR(cpu);
break;
case 7:
printf("x%04X: x%04hX ", order, old_pc);
instr_STR(cpu);
break;
case 8:
printf("x%04X: x%04hX ", order, old_pc);
instr_RTI(cpu);
break;
case 9:
printf("x%04X: x%04hX ", order, old_pc);
instr_NOT(cpu);
break;
case 10:
printf("x%04X: x%04hX ", order, old_pc);
instr_LDI(cpu);
break;
case 11:
printf("x%04X: x%04hX ", order, old_pc);
instr_STI(cpu);
break;
case 12:
printf("x%04X: x%04hX ", order, old_pc);
instr_JMP(cpu);
break;
case 13:
printf("x%04X: x%04hX ", order, old_pc);
instr_err(cpu);
break;
case 14:
printf("x%04X: x%04hX ", order, old_pc);
instr_LEA(cpu, order);
break;
case 15:
printf("x%04X: x%04hX ", order, old_pc);
instr_TRAP(cpu);
break;
default:
printf("Bad opcode: %d; quitting\n", (Commands.opCode)); // ** Note ** place "op(cpu->instr_reg))"
cpu->running = 0;
}
old_pc++;
}
